Lateral boring system

ABSTRACT

A lateral boring device for effective utility installation under sidewalks, driveways, and other obstacles. The present invention utilizes a hand-held drill, a flexible shaft, a blade attachable to the flexible shaft, and a metal sock. The operator of the present invention makes an incision into the ground with the blade in close proximity to the obstacle intended to be circumvented. The operator commences boring, and the flexible shaft begins to descend below the ground and underneath the obstacle. The low power of the drill prevents the flexible shaft from continuing to descend below the hardpan, and cause the flexible shaft to bend in a generally upwardly horizontal direction. The low power of the drill also prevents the flexible shaft or the blade from causing damage to the underside of the obstacle, and eventually the flexible shaft resurfaces on the opposite side of the obstacle. Upon resurfacing, the operator removes the blade and attaches the sock, which can be coupled to the length of wire, pipe or conduit and pulled back through the bore hole.

BACKGROUND OF INVENTION

Typically wire, cabling, pipe and other equipment installed for providing power, signal, water, or some other medium are placed underground. The reasons for this are to protect and insulate the medium passing through this equipment, and also to eliminate the unpleasing aesthetic appearance of the multitude of these wires, cables and pipes necessary to provide buildings with the necessary utilities and services.

One prior method for placing these types of underground equipment was to dig a trench along the path desired to place the equipment. The equipment could be placed in the bottom of the trench and covered up. One disadvantage of this method was the damage to the land caused by the trenching. Another disadvantage is the damage to permanent structures in the path of the equipment, such as sidewalks, driveways, highways and other surfaces.

Currently there are a variety of boring methods for alleviating the disadvantages inherent with trenching. Some of theses devices are disclosed in U.S. Pat. Nos. 5,584,351, 5,880,680, 5,490,569 and 5,070,948. These boring devices require heavy machinery to drive the shaft of the device, and typically require sophisticated guidance systems, including sensors and processors, to achieve proper alignment of the shaft of the device. One disadvantage of these systems is the expense required to complete the boring. Another disadvantage is the complexity of the method, in particular the operation of the guidance system to ensure proper alignment. Despite the cost and the complexity of these systems, the borehole path is seldom straight, and the exit point of the boring device is uncertain.

Thus, there is a present need for a boring device that is less expensive, easier to operate, and can more accurately place the exit point of the boring shaft. In particular, there is a need for a device that does not require heavy machinery or a guidance system to operate.

SUMMARY OF INVENTION

The present invention solves these problems and others by providing a simple and effective lateral boring device for underground installation of utility equipment. The device consists of a hand-held drill, a flexible shaft attachable at one end to the drill, a bit and blade attachable to the other end of the flexible shaft, and a metal sock for retrieving the utility equipment after the boring has been completed.

In a preferred embodiment of the invention, the bit is coupled to the flexible shaft and an incision is made into the soil adjacent to the obstacle that it is desired to circumvent. The operator of the device will then couple the other end of the flexible shaft to the hand-held power unit and begin to drill in a generally downwardly horizontal direction. The low power of the drill does not enable the flexible shaft to extend deeper than the hardpan beneath the ground soil, nor does it allow the blade to penetrate through the obstacle material. By angling in a generally downward direction, the flexible shaft will encounter harder material and begin to bend back in a generally upward direction. Eventually it will either resurface cleanly at the other end of the obstacle or slide along the underside of the obstacle until it resurfaces.

Another aspect of the invention allows the user to adjust the angle of entry to accomplish longer or shorter runs more effectively, and reduce the overall length of the borehole.

Yet another aspect of the invention is the use of metal sock in place of the bit and blade for attaching the utility line equipment and retracting that equipment back through the borehole.

These and other features of the present invention are evident from the drawings along with the detailed description of preferred embodiments. (For a fuller understanding of the nature and advantages of the invention, reference should be made to the ensuing detailed description taken in conjunction with the accompanying drawings.)

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a detail view of a lateral boring system of a preferred embodiment of the present invention;

FIG. 2 is a view of the drill shaft adapter of the embodiment of FIG. 1;

FIG. 3 is a detail view of the opposite end of the shaft as the one shown in FIG. 1, attached to a bit of a preferred embodiment;

FIG. 4 is an exploded view of the same end of the drill shaft as shown in FIG. 3 with the drill bit of a preferred embodiment;

FIG. 5 is an exploded view of the same end of the drill shaft with a sock attachment of a preferred embodiment.

DETAILED DESCRIPTION

The present invention provides a tool capable of laterally boring for the placement of underground cables, wires, pipe and other equipment. Referring in more detail to the drawings, as shown in FIGS. 1-5, a preferred embodiment of the present invention is described. It is to be expressly understood that this exemplary embodiment is provided for descriptive purposes only and is not meant to unduly limit the scope of the present inventive concept. Other embodiments, and variations of the hand-held drive assembly or flexible shaft of the present invention are considered within the present inventive concept as set forth in the claims herein. For explanatory purposes only, the apparatus of the preferred embodiments are discussed primarily for the purposes of understanding the method of underground boring. It is to be expressly understood that other boring equipment are contemplated for use with the present invention as well.

A preferred embodiment of the present invention is illustrated in FIG. 1. The boring system 10 includes a power drill 20, flexible drill shaft 30 and drill bit 50. The power drill 20, of this preferred embodiment, is a standard three quarter inch hand held power drill. It is to be expressly understood that other types of drills could be used, including different sizes and power ranges, as well as a mounted drilling device as well. These can include industrial portable gas powered units, hydraulic units or other tools that can provide rotational power to the flexible drill shaft.

The flexible drill shaft 30 includes a drill end adapter 32. The drill end adapter 32 includes an engagement end 34 that is inserted into the chuck 22 of the drill 10, hexagonal flattened surfaces 36 for receiving an open end wrench and a threaded portion 38. The engagement end 34, in this preferred embodiment, may include several flattened surfaces for minimizing slippage relative to the drill during use.

The flexible drill shaft 30 also includes an extended member 40 formed of a relatively hard steel or other material. In this preferred embodiment the extended member 40 is formed from structural reinforcement steel bars commonly referred to as rebar. This material is typically used in forming concrete structures to provide reinforcement and stability to concrete slabs. It is to be expressly understood that other types of materials may also be used having a relatively small diameter compared to the length of the rod. In the preferred embodiment, the extended member 40 is approximately ten feet in length and having a diameter of between one-half inch and one inch. This provides a relatively flexible drill shaft over the length of the extended member while still providing a drill shaft capable of high torque strength. The rebar or other drill shaft material while stiff over a short length is relatively flexible over the distance of ten feet. It is capable of deflecting up to several feet over that length. Other lengths and diameters may also be used within the scope of the present invention. The rebar or other drill shaft material may be cut into any length desired. However, it is important that length be sufficient that adequate flexibility is maintained.

As shown in FIG. 2, a female threaded portion 42 is attached to the proximal end of the shaft 40, as shown in FIG. 2. This threaded portion may be machined onto the shaft 40, welded or otherwise fastened onto the shaft end. This threaded portion 42 is engageable with the threaded portion 38 of the adaptor 32 to fasten the drill shaft 40 to the adapter 32. A male threaded portion 44 is formed on the distal end of the shaft 40. This portion may also be machined directly onto the shaft, welded onto the shaft or otherwise fastened to the shaft.

Drill bit 50, shown in FIG. 3, includes a female threaded portion 52 that engages with the threaded portion 44 of the shaft 40. This allows the drill bit 50 to be replaceable as discussed below as well as to be replaced when worn. It is to be expressly understood that the gender of the threaded portions may be reversed, or the drill bit may be permanently attached to the drill shaft by welding or other attachment techniques. The drill bit 50 includes a blade portion 54. In the preferred embodiment, the blade portion 54 is formed of two standard washers welded together at an angle to one another to create the blade. It is to be expressly understood that other types of drill heads such as used in tunneling, boring or other drilling operations could be used as well.

The drill system 10 also, in one preferred embodiment, a sock attachment 60, as shown in FIG. 5. The sock attachment includes a threaded portion 62 that can be attached to the threaded portion 44 formed on the drill shaft 40. The sock attachment also includes an attachment device 64. The attachment device can include a loop 66 attached to the sock attachment 60 with a clamp 68 that can secure a cable, wire, pipe or other equipment that is to be pulled through the bore created by the drill system 10.

In use, the drill adapter 30 is attached to the drill shaft 40. The drill adapter is then secured in the chuck of the drill 20. The drill bit 50 is attached to the drill shaft 40 as well. The drill operator excavates an initial hole spaced a short distance from the object that is to be bored beneath, such as a sidewalk, driveway or other structure. The distance can be around three feet or so. The operator angles the drill shaft 40 into the hole and commences boring by activating the drill to start rotation of the drill bit 50. As the boring process continues, the blade begins to slowly angle towards the surface and the flexible drill shaft 40 bends slightly with the blade. This upward movement is due to the natural tendency of the flex in the drill shaft encountering resistance. The upward movement is also a result of the ground normally becoming more dense and hard as the drill bit goes downward and may also be assisted by the hard pack under the object as well as rocks, roots and other encountered objects.

Eventually, the drill bit 50 makes contact with the bottom of the obstacle. There is not enough power generated from the hand-held drill for the drill bit to penetrate the surface of the obstacle. The drill bit 50 continues to bounce along the bottom of the obstacle until it passes beyond the obstacle, at which point it resurfaces on the opposing side of the obstacle.

Upon resurfacing, the drill bit 50 is disconnected and the sock attachment 60 is secured to the drill shaft 40. The free end of the length of cable, wire, or pipe that is intended to be buried is secured to the attachment device 68 of the sock attachment 60. The cable, wire, or pipe is than pulled back through the hole that has just been created by removing the drill shaft 40 from the hole in the opposing direction that it has just traveled.

Additional lengths of drill shaft may be added onto if required during the boring operation. For example, up to ten lengths of the ten foot long drill shaft 40 discussed above may be engaged with one another to bore a one hundred foot length bore.

In another embodiment, the operator may use a more powerful drive unit than the drill 10 described above for boring through particularly hard or dense material. Also, commercial drilling or boring units that are known in the industry may be used. These units often contain a hydraulic power pack and/or may use a self contained power generation unit.

Also, in other preferred embodiments, the drill bit 50 may use more or fewer than two washers are welded to the threaded shaft 52. In yet another alternative embodiment, any small piece of material strong enough to be securely attached to the end of the flexible shaft of the drill shaft 40 may be used to form the blade of the bit. Although not specifically disclosed herein, similar pieces of material that may accomplish this function are considered within the scope of the claimed invention.

As will be understood by those familiar with the art, the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. For example, the present invention is not limited in the number or type of flexible shafts that may be operated by the hand-held drive device. Accordingly, the disclosure of the preferred embodiment of the invention is intended to be illustrative, but not limiting, of the scope of the invention which is set forth in the following claims. 

1. A lateral boring device, comprising: a flexible shaft; a drill bit attached to said flexible shaft; and a hand-held drive assembly; said hand-held drive assembly capable of providing power for rotation and thrust sufficient to move said flexible shaft through soil and insufficient to move said flexible shaft through rock or concrete.
 2. The device of claim 1 wherein said flexible shaft is formed from structural reinforcement bars.
 3. The device of claim 1 wherein said flexible shaft is formed from medium gage steel.
 4. The device of claim 1 wherein said flexible shaft is formed from light gage steel.
 5. The device of claim 1 wherein said flexible shaft includes plurality of shafts, coupled together to increase the length of the borehole.
 6. The device of claim 1 wherein said drill bit is formed from: two washers secured to one another at an angle to one another.
 7. The device of claim 1 wherein said device further includes: a sock attachment for engagement on said flexible shaft; and an attachment device on said sock attachment for securing an object to be pulled through the hole created by said device.
 8. The device of claim 1 wherein said device further includes: an adapter for attaching said flexible shaft to said drive assembly.
 9. The device of claim 1 wherein said device further includes: an attachment mechanism for removably securing said drill bit to said flexible shaft.
 10. A method for boring underneath a hard surface, comprising; positioning a bit attached to a flexible shaft adjacent to a hard surface, and angling the shaft in a generally downwardly horizontal direction; coupling said flexible shaft to a hand-held power device for providing rotation and thrust to said flexible shaft; driving said flexible shaft beneath a hard surface until said flexible shaft begins to bend in a generally upwardly horizontal direction; and continuing to drive said flexible shaft beneath a hard surface until said flexible shaft either surfaces or contacts the underside of the hard surface, causing said flexible shaft to slide horizontally until it surfaces on the other side.
 11. The method of claim 10 wherein said method further includes: retrieving an object through the hole that has been created by attaching the object to said flexible shaft; and retracting said flexible shaft from underneath the hard surface.
 12. The method of claim 11 wherein said step of retrieving an object further includes: securing a sock attachment to said flexible shaft; and engaging the object with said sock attachment.
 13. The method of claim 10 wherein said method further includes: attaching additional lengths of flexible shafts to said flexible shaft to extend the length of the hole being bored. 